Genius speakers set for PC - SJ2025 audio amp

Discussion in 'General Electronics Chat' started by atferrari, Nov 25, 2014.

  1. atferrari

    Thread Starter AAC Fanatic!

    Jan 6, 2004
    Genius speakers set for PC. Model SP-E120

    Audio amp inside is SJ2025. I could find the datasheet in Chinese language only.

    After replacing the dual pot damaged when falling from a desk, I noticed that at low level (pot progressively CCW) the audio output is more and more blurred, the lower the noisiest. That is awful!

    With the pot fully CW, (maximum output), no matter what input, audio in the speakers is good.

    The IC is hot to touch but I see that in the bottom, 4 pins (2 on each side) are soldered to what I believe is a thermal pad, with a generous amount of solder.

    My daughter insists that in the past it worked OK at low levels.

    At least I would like to know what to look at before giving up here. Two pots already changed and the main filter cap as well. Caps look OK, no leaking nor bulging.

    Self esteem is at stake here.

    Gracias for any help.
    Last edited: Nov 25, 2014